JP2000255137A - Printing head supporting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing head supporting device capable of easily replacing recording paper or an ink ribbon without generating wrinkles therein. SOLUTION: A printing head supporting device is equipped with a shaking member 12 having a printing head 11 mounted thereon, the first pivot shaft 14 provided in parallel to a platen roller 13 to support the shaking member 12 in a freely shakable manner, the second support shaft 15 which is arranged in the vicinity of one end of the platen roller 13 along the direction crossing the platen roller 13 almost at a right angle and to which the first pivot shaft 14 is attached at a right angle, the stopper bringing the first pivot shaft 14 and the printing head 11 into engagement with each other in a state parallel to the platen roller 13 by the engagement with the first support shaft, and a temporary engaging mechanism allowing the printing head 11 to be spaced apart from the platen roller 13 by a predetermined distance by the engagement with the shaking member 12 in such a state that the first pivot shaft 14 is engaged with the stopper.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print head supporting apparatus for supporting a print head such as a thermal head of a thermal printer, and more particularly, to a print head which presses against a platen roller to perform printing. The present invention relates to a print head support device suitably used for supporting a print head.

[0002]

2. Description of the Related Art Conventionally, for example, in a thermal printer, as shown in FIG. 7, a recording paper 1 wound in a roll, an ink ribbon 2 for thermal transfer, a print head 3, and the print head 3 are pressed against each other. The recording paper 1 and the ink ribbon 2 are inserted between the print head 3 and the platen roller 4 in a state where the recording paper 1 and the ink ribbon 2 are overlapped with each other. The recording paper 1 and the ink ribbon 2 are sandwiched between the rollers 4 by pressing the rollers 4 at a predetermined pressure,
While the recording paper 1 and the ink ribbon 2 are being conveyed by the platen roller 4, the ink ribbon 2 is heated by the print head 3, and the ink on the ink ribbon 2 is thermally transferred to the recording paper 1, whereby the recording is performed. Printing is performed on paper 1.

On the other hand, when it is necessary to replace the recording paper 1 and the ink ribbon 2 due to consumption, the print head 3 is separated from the platen roller 4 as shown in FIGS. 8 and 9, for example. Later, in these gaps,
This is performed by inserting the recording paper 1 and the ink ribbon 2 from one end of the platen roller 4 as shown by arrows in FIG.

By the way, in such a conventional structure, when the recording paper 1 and the ink ribbon 2 are replaced, the recording paper 1 and the ink ribbon 2 are inserted into a gap between the print head 3 and the platen roller 4. The work of inserting from one end side of the platen roller 4 is required. However, since the gap is often set to be small due to dimensional restrictions of the printer, the recording paper 1 and the ink ribbon 2 need to be inserted. There is a problem that it cannot be performed smoothly. In addition, when the recording paper 1 and the ink ribbon 2 are inserted, they may come into contact with the print head 3 and the platen roller 4 to cause wrinkles or breakage.

Therefore, conventionally, for example, Japanese Patent Laid-Open No.
Japanese Patent Laid-Open No. 39890 proposes a technique capable of solving the above-mentioned problem. As shown in FIG. 10 and FIG. 11, this technique is used near the one end of the platen roller 4.
A pivot 5 is provided along a direction orthogonal to the platen roller 4, and the ink ribbon 2 and one end of the print head 3 are swingably supported by the pivot 5, and the recording paper 1 and the like are At the time of replacement, the ink ribbon 2 and the print head 3 are swung about a pivot 5 as shown by a solid line in FIG. 10 so that the upper part of the platen roller 4 and the lower part of the print head 3 are largely opened. The replacement of the ink ribbon 2 and the recording paper 1 is performed by using the largely open space. After the replacement of the ink ribbon 2 and the recording paper 1 is completed, the ink ribbon 2 and the print head 3 are replaced.
Is swung in the opposite direction, and then the print head 3 is brought into pressure contact with the platen roller 4 as shown by a chain line in FIG. With such a configuration, when the recording paper 1 and the ink ribbon 2 are replaced, the interference of the recording paper 1 and the ink ribbon 2 with the print head 3 and the platen roller 4 is reduced, and the replacement operation is simplified. There is.

[0006]

However, the above-mentioned prior art still has the following problems to be improved. That is, after the recording paper 1 and the ink ribbon 2 are remounted, the print head 3 is again pressed against the platen roller 4 in the process of pressing the print head 3 against the platen roller 4 from the end on the pivot 5 side. The contact gradually comes to the end. This is a phenomenon that occurs because the print head 3 is configured to be supported via an elastic member so that the print head 3 elastically contacts the platen roller 4 in a use state. When the print head 3 is gradually brought into contact with the platen roller 4 from one end to the other end, the recording paper 1 positioned on the platen roller 4 or the print head 3 One end (the end on the pivot 5 side) of the ink ribbon 2 located on the lower surface of the ink ribbon 3 is moved so as to be pushed out toward the other end, and as a result, as shown in FIG. The paper 1 (ink ribbon 2) has a problem that it undulates and wrinkles are formed.

[0007] The present invention has been made in view of such conventional problems, and facilitates replacement of a recording paper or an ink ribbon or the like, and allows replacement without causing wrinkles on the ink ribbon or the recording paper. It is an object of the present invention to provide a printhead supporting device that can be used.

[0008]

According to a first aspect of the present invention, there is provided a print head support mechanism for supporting a print head opposed to a platen roller in order to achieve the above object. A swing member on which the print head is mounted, provided in parallel with the platen roller, and swingably supporting the swing member,
A first pivot for relatively moving the print head while holding the print head parallel to the platen roller, and disposed near an end of the platen roller in a direction substantially orthogonal to the platen roller, and When the first pivot is engaged with a second pivot on which the first pivot is mounted orthogonally, the first pivot and the print head are locked in parallel with the platen roller. A stopper for temporarily holding the print head at a predetermined distance from the platen roller by engaging the swinging member in a state where the first pivot is locked by the stopper; In a state in which the swing member is disengaged from the temporary locking mechanism, the swing head is engaged with the swing member to keep the print head in contact with the platen roller. Characterized in that it comprises a locking mechanism for. According to a second aspect of the present invention, there is provided the print head supporting device according to the first aspect, wherein an auxiliary swing member is provided to cover the swing member, and the auxiliary swing member is swung by the first pivot. While being movably supported, a resilient member is provided between the swinging member and the auxiliary swinging member for urging the swinging member and the auxiliary swinging member in a direction in which the swinging member and the auxiliary swinging member are separated from each other. A temporary locking mechanism and a locking mechanism are provided between the auxiliary swinging member and the auxiliary swinging member.

According to the print head support device of the present invention, when the print head is swung about the second pivot, the print head is at a large angle with respect to the platen roller. Rocked. As a result, a large space is formed around the platen roller and the print head, and the recording paper or the like can be easily mounted. Then, when the swing member is swung in the opposite direction to return the print head to the use state again, the first pivot is engaged with the stopper, so that the first pivot and the print head are connected to the platen roller. The print head is held in a state where the print head is separated from the platen roller by a predetermined distance by the swing member being engaged with the temporary locking mechanism. Thus, in a state where the engagement between the swinging member and the temporary locking mechanism is released, after swinging the swinging member toward the platen roller, the swinging member is fixed by the lock mechanism. . In this state where the swinging member is locked by the temporary locking mechanism, the print head is held at a distance from and parallel to the platen roller, and the swinging operation of the swinging member is followed by the swinging member. Is swung about a first pivot locked parallel to the platen roller, so that the print head is moved while maintaining the parallel state toward the platen roller. Is pressed against. Therefore, the recording paper, the ink ribbon, and the like positioned between the print head and the platen roller are sandwiched between the print head and the platen roller almost simultaneously over the entire length in the width direction.
An auxiliary swinging member is provided so as to cover the swinging member, and the auxiliary swinging member is swingably supported by the first pivot shaft. A resilient member is provided between the moving member and the auxiliary rocking member to urge the rocking member and the auxiliary rocking member in a direction away from each other, and the temporary locking mechanism and the lock mechanism are connected to the auxiliary rocking member. The print head can be pressed against the platen roller with a predetermined elastic force.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. In these drawings, reference numeral 10 denotes a print head support device according to the present embodiment. The print head support device 10 includes a swing member 12 on which a print head 11 is mounted,
Is provided in parallel with a platen roller 13 pressed in parallel, and supports the swing member 12 in a swingable manner, so that the print head 11 is relatively moved while being held in a parallel state with respect to the platen roller 13. First Axis 1
4, and disposed near one end of the platen roller 13 along a direction substantially orthogonal to the platen roller 13;
When the first pivot 14 is engaged with the second pivot 15 to which the first pivot 14 is attached in an orthogonal state, the first pivot 14 and the print head 11 are connected to the platen. A stopper 16 that is locked in a state parallel to the roller 13, and the print head 11 is fixed to the platen roller by the swing member 12 being engaged in a state where the first pivot 14 is locked by the stopper 16. And a temporary locking mechanism 17 (see FIG. 3) kept at a predetermined distance from the swinging member 13 in a state where the swinging member 12 is disengaged from the temporary locking mechanism 17. In addition, a basic configuration including a lock mechanism 18 (see FIG. 3) for holding the print head 11 in contact with the platen roller 13 is provided.

The platen roller 13 is rotatably supported at both ends by a base plate 19 fixed to a printer main body (not shown). Is to be rotated.

On the other hand, in the present embodiment, an auxiliary swinging member 20 is provided to cover the swinging member 12, and the auxiliary swinging member 20 is swingably supported by the first pivot 14. At the same time, a resilient member 21 is provided between the swinging member 12 and the auxiliary swinging member 20 to urge the swinging member 12 and the auxiliary swinging member 20 in a direction in which they are separated from each other. The resilient member 21 is connected to the swinging member 12.
And is provided so as to surround a guide rod 22 provided so as to protrude from the upper surface and slidably penetrate the auxiliary swinging member 20. In addition, the guide rod 2
2 and the resilient member 21 are provided at two places at intervals in the axial direction of the platen roller 13. Further, an engagement ring 23 is fixed to an end of each of the guide rods 22 on a side protruding from the auxiliary swing member 20, and these engagement rings 23 are attached to the auxiliary swing member. By being engaged with the upper surface of the pivot 20, the maximum opening angle of the pivoting member 12 and the auxiliary pivoting member 20 around the first pivot 14 is regulated.

In the present embodiment, the second pivot 15 is divided into two parts and fixed to the base plate 19 so as to be coaxial with each other, as shown in FIG. The pivot 15 positioned above in FIG. 2 is rotatably supported by a bearing 24 mounted on the base plate 19.
The second pivot 1 supported by the bearing 24
An L-shaped bracket 25 is integrally attached to the bracket 5. One end of the first pivot 14 is fixed to the bracket 25 so that the first pivot 14 and the second The pivot 15 is connected in an orthogonal state.

On the other hand, as shown in FIGS. 2 and 3, a concave portion is formed in the upper end surface of the side of the base plate 19, into which the other end of the first pivot 14 is inserted. The stopper 16 of the present embodiment is configured so that the first pivot 14 is parallel to the platen roller 13 when one end of the first pivot 14 is inserted and locked. , The position is set.

Further, the first swinging member 20 is provided with the first
At the end opposite to the side supported by the pivot 14 of
A flange 26 which is overlapped with the other (lower in FIG. 1) second pivot 15 is provided continuously, and a long groove 27 is formed in the flange 26 along the swing direction of the auxiliary swing member 20. Have been. As shown in FIG. 1, the second pivot 15 is slidably fitted in the long groove 27 so as to guide the swing of the auxiliary swing member 20.

A substantially U-shaped locking member 28 is provided on the base plate 19 so as to extend along the bottom surface and both side surfaces of the base plate 19.
On both sides, a pair of pins 8 are swingably connected to both side surfaces of the base plate 19 by a pair of pins 29. As shown in FIG. 3, locking projections 28 a are integrally provided on upper ends of both side surfaces of the locking member 28, respectively. Engaging legs 20a are formed on the engaging projections 28a to be engaged from below, and the lower ends of the engaging legs 20a are brought into contact with the engaging projections 28a, whereby the auxiliary swinging member 20a is engaged. Is temporarily stopped. Therefore, these engaging legs 20a and the locking projections 28a constitute the temporary locking mechanism 17 of the present embodiment. Further, a contact portion between the locking projection 28a and the engaging leg 20a is formed as a contact surface inclined with respect to the swinging direction of the auxiliary swinging member 20, so that the auxiliary swinging member 20 is locked. When forcibly swinging toward the member 28, the engaging leg 20a smoothly slides below the locking projection 28a. At the tip of the engaging leg 20a, an engaging piece 20b is provided to be engaged with the engaging projection 28a of the engaging member 28 from below. The engaging piece 20b engages with the engaging projection 28a. The upward movement (in the direction away from the platen roller 13) of the auxiliary swinging member 20 is restricted by the engagement with the mating piece 20b. The locking projection 18a forms the lock mechanism 18 of the present embodiment.

Further, in FIG. 3, reference numeral 30 denotes a positioning pin for restricting a rotational position of the engaging member 20 in the direction of engagement with the engaging leg 20a by bringing the locking member 28 into contact therewith. Indicates a resilient member that urges the locking member 28 in a direction for engaging the engaging leg 20a.
When the locking member 28 is brought into contact with the positioning pin 30, the positioning member 30 moves the locking member 28 to a locking projection 28 a provided on the locking member 28 and the auxiliary swinging member 20. Are brought into contact with each other and held in position.

Next, the operation of the present embodiment configured as described above will be described. First, in a usable state as shown in FIG. 1, the auxiliary swinging member 20 is moved to the position shown in FIG.
As shown in FIG. 7, the engaging piece 20b is engaged with the locking projection 28a of the locking member 28. In this state, the print head 11 is pressed against the platen roller 13 and By compressing 21, the print head 11 is uniformly pressed against the platen roller 13 with a predetermined pressure over the entire length with the auxiliary swinging member 20 as a support. When printing, the ink ribbon and the recording paper (reference numeral 1 in FIG. 2) sandwiched between the print head 11 and the platen roller 13 are used.
Is sent out by the rotation of the platen roller 13 and the print head 11 is operated, whereby the recording on the recording paper 1 is performed.

When it is necessary to replace the recording paper 1 or the ink ribbon, first, after the fixing of the lock mechanism 18 is released, the auxiliary swinging member 20 is swung about the second pivot 15. Move. By such operation,
The auxiliary oscillating member 20 is oscillated together with the oscillating member 12 and the print head 11 so as to be separated from the platen roller 13, and the upper part of the platen roller 13 is largely opened as shown in FIG. In this state, the recording paper 1 is placed on the platen roller 13 or the ink ribbon mounted on the upper surface of the auxiliary swinging member 20 is replaced, and a part of the ink ribbon is set on the lower surface side of the print head 11. I do.

Next, the auxiliary swinging member 20 is swung about the second pivot 15 toward the platen roller 13, and the end of the first pivot 14 is inserted and fitted into the stopper 16. In this state, the print head 11 is in a state parallel to the platen roller 13.

Next, the auxiliary oscillating member 20 and the oscillating member 12 are oscillated about the first pivot 14. In the course of the oscillating operation, the engaging leg 20a of the auxiliary oscillating member 20 is moved. As shown in FIG. 3B, when the tip is brought into contact with the tip of the locking projection 28a of the locking member 28, the swinging operation is temporarily stopped. this is,
Since the rotation of the locking member 28 is elastically restrained by the biasing force of the resilient member 31, the locking is performed by applying resistance to the auxiliary swinging member 20 by the above-described contact (that is, the locking member 28 is rotated). The auxiliary swinging member 20 is locked by the temporary locking mechanism 17). In such a temporarily locked state, the auxiliary swinging member 20 and the swinging member 12
Since the first pivot 14 is swung around the first pivot 14 which is in parallel with the platen roller 13,
And the platen roller 13
The print head 11 is held in a non-contact state with the platen roller 13 by the temporary locking function of the temporary locking mechanism 17 described above, as shown in FIG. Therefore, in this state, the print head 11, the platen roller 13, and the recording paper 1
(Or ink ribbon) are made parallel, and the recording paper 1 and the print head 11 are kept in a non-contact state.

As a result, when the auxiliary swinging member 20 is forcibly swung toward the platen roller 13, as described above, the contact surface between the engaging leg 20a and the locking projection 28a is
By being inclined with respect to the swinging direction of the auxiliary swinging member 20, the locking projection 28a is
As a result, the engaging piece 20b of the engaging leg 20a moves over the locking projection 28a and is positioned below the engaging projection 20a. Prior to the engagement piece 20b of the engagement leg 20a getting over the locking projection 28a, as shown in FIG.
Is brought into contact with the platen roller 13 via the recording paper 1. Further, when the swinging of the auxiliary swinging member 20 is continued, the movements of the print head 11 and the swinging member 12 are stopped, and only the auxiliary swinging member 20 performs the swinging operation. When each of the resilient members 21 interposed between the rocking member 12 and the rocking member 12 is compressed, and when the engagement piece 20b passes over the locking protrusion 28a, the locking member 28 The urging member 31 is caused to swing toward the original position by the urging force, whereby the locking projection 28a is engaged with the engagement piece 20b from above. As a result, the function of the lock mechanism 18 restrains the swinging of the auxiliary swinging member 20 in the direction away from the platen roller 13, and the urging force of the resilient member 21 causes the print head 11 to move the recording paper 11. 1 and is brought into pressure contact with the platen roller 13 to be set in a recordable state.

Then, as described above, the print head 11
During the operation of pressing the print head 11 against the platen roller 13, the print head 11 is always kept parallel to the platen roller 13, so that the recording paper 1 or the ink ribbon pressed against the platen roller 13 is almost simultaneously moved over its entire width. It is pressed against the platen roller 13. As a result, when the recording paper 1 and the ink ribbon are remounted, they can be mounted favorably without wrinkles.

It should be noted that the shapes, dimensions, and the like of each component shown in the above-described embodiment are merely examples, and can be variously changed based on design requirements and the like.

[0025]

As described above, according to the present invention,
When replacing the recording paper or ink ribbon, etc., the gap between the print head and the platen roller is greatly opened to facilitate the replacement, and when the print head and the platen roller are pressed against each other, they are kept in parallel. As a result, the ink ribbon and the recording paper can be reliably sandwiched without wrinkles.

[Brief description of the drawings]

FIG. 1 is a front view of a main part showing an embodiment of the present invention.

FIG. 2 is a plan view of a main part showing one embodiment of the present invention.

FIG. 3 shows one embodiment of the present invention, wherein (a)
FIG. 4B is a side view for explaining the function of the lock mechanism.
It is a side view for explaining the function of a temporary locking mechanism.

FIG. 4 is a view for explaining functions of the embodiment of the present invention, and is a front view showing a state in which an auxiliary swinging member is separated from a platen roller.

FIG. 5 is a view for explaining functions of the embodiment of the present invention, and is a front view showing a state in which the auxiliary swinging member is being closed.

FIG. 6 is a view for explaining the function of the embodiment of the present invention, and is a front view showing a state in which the print head is pressed against the platen roller while the auxiliary swinging member is being closed.

FIG. 7 is a schematic side view showing a conventional example of a printer.

FIG. 8 is a schematic side view showing a conventional example of a printer, in which a recording paper and an ink ribbon can be replaced.

FIG. 9 is a schematic side view illustrating a conventional example of a printer and illustrating an operation of replacing a recording paper or an ink ribbon.

FIG. 10 is a front view showing another conventional example, showing a movement of a print head during a replacement operation of a recording paper or an ink ribbon.

FIG. 11 is a front view showing another conventional example, showing a state in which the print head is rotated halfway during the operation of replacing the recording paper or the ink ribbon.

[Explanation of symbols]

 Reference Signs List 10 print head support device 11 print head 12 swing member 13 platen roller 14 first pivot 15 second pivot 16 stopper 17 temporary locking mechanism 18 lock mechanism 19 base plate 20 auxiliary swing member 20a engagement leg 20b engagement piece 21 Spring member 22 Guide rod 23 Engagement ring 24 Bearing 25 Bracket 26 Flange 27 Long groove 28 Lock member 28a Lock projection 29 Pin 30 Positioning pin 31 Spring member

Claims (2)

[Claims] 1. A print head support mechanism for supporting a print head opposed to a platen roller, comprising: a swing member on which the print head is mounted; and a swing member provided in parallel with the platen roller. A first pivot for supporting the print head relative to the platen roller while supporting the print head in a parallel state, and a direction substantially orthogonal to the platen roller near one end of the platen roller; And the first pivot is engaged with the second pivot, the first pivot being mounted perpendicular to the first pivot, and the first pivot and the print head are engaged with each other. A stopper that is locked in a state parallel to the platen roller, and a front end is formed by the swing member being engaged in a state where the first pivot is locked by the stopper. A temporary locking mechanism for keeping the printing head away from the platen roller by a predetermined distance; and a state in which the rocking member is engaged with the rocking member in a state where the locking member is disengaged from the temporary locking mechanism. A lock mechanism for holding the print head in contact with the platen roller. 2. An auxiliary swinging member is provided to cover the swinging member, the auxiliary swinging member is swingably supported by the first pivot, and the swinging member and the auxiliary swinging member are provided. A resilient member for urging the swing member and the auxiliary swing member in a direction to separate them from each other is provided between the movable member and the temporary locking mechanism and the lock mechanism. The print head support device according to claim 1, wherein the print head support device is provided.